Friday, 9 August 2013

A supernova is a stellar explosion that is more energetic than a
nova. Supernovae are extremely luminous and cause a burst of radiation
that often briefly outshines an entire galaxy, before fading from view
over several weeks or months.

During this short interval a supernova can radiate as much energy as
the Sun is expected to emit over it's entire life span. The explosion
expels much or all of a star’s material. Supernovae can be triggered in
one of two ways: The sudden reignition of nuclear fusion in a degenerate
star; or by the collapse of the core of a massive star.

Back on July 4 of 1054, a supernova was seen by Chinese, Arab, and
possibly Amerindian observers near the star Zeta Tauri. For several
months it remained bright enough to be seen during the day! The remnant
of SN 1054, which consists of debris ejected during the explosion, is
known as the Crab Nebula.